How to do technical drawings

Written by steven yessick| 13/05/2017

Technical drawings are a useful means of creating a design. By creating a technical drawing, you can help the architect understand your preliminary design ideas more clearly. Technical drawings are useful for home designs, renovations, product development and for inventions. Having a nice-looking drawing to present to the designer helps her to gain a clear understanding of the approach that you would prefer.

Draw the object you would like to draft freehand. This drawing does not have to be perfect. Draw it with pencil on trace paper. Draw several design options in this manner. Use arrows to point to parts of the rough sketch to make notes of what is needed in the design.

Take the preliminary sketch and tape it to the table. Place another piece of trace paper over the rough sketch. This time use the art pen and the 30/60/90 triangle to make a rough draft of the design. For curves in the design, use either a circle template or French curves. A wide variety of curves are available with the use of French curves. Make notes to the side of the drawing.

Next, clear off the table and put the rough draft to the side. Start a new drawing and scale this drawing with the scale ruler. Measurements are essential. A scale of 2 inches equals 1 foot would be useful for something roughly the same size as cabinetry. A technical drawing has to have the appropriate measurements. Use the rough draft as a scaled example of the design. The rough draft should be the groundwork for the finalised drawing.

Draw the design to scale in pencil on a piece of vellum using a light pencil. Technical drawings are usually drawn in three dimensions as well as in two dimensions. Use a 90-degree angle to draw the object three dimensionally. The corner should face the viewer and the lines which extend from the base and top of the drawing should encompass a 90-degree angle from one side to another. This is called an axonometric drawing. Draw details of the design at a larger scale to inform the builder or manufacturer on how the design should be built.

Draw the finalised drawing in pen on vellum. Go over the pencil lines with a pen. Vellum is a nice paper for technical drawings. You can find it at most art supply stores. Use the art pen with the adjustable triangle. It is recommended that pennies are taped to the bottom of the triangle to prevent the ink from smearing. Be careful not to smudge the wet ink. Draw it from top to bottom. Use the scale and light pencil marks to measure. Draw the axonometric in order to illustrate what the design looks like from all sides. Include measurements by drawing a straight line with marks on the end of the line. Place the measurements on the outside of this line. All drawings should include measurements. The draftsman can also make notes on the side of the final drawing to specify functions, materials used and elements in the drawing that could be modified.

Tip

Use care when drafting; don't let your pen slip. Always use some sort of straight edge or ruler to draw straight lines. Draw each side of the object in two dimensional form with notes. Draw design details in two or three dimensional form.

Tips and warnings

Use care when drafting; don't let your pen slip. Always use some sort of straight edge or ruler to draw straight lines.